Linked Life Data

2899462

Source:http://linkedlifedata.com/resource/pubmed/id/2899462

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1988-8-31
pubmed:abstractText
We have used two different cultured cell lines--S49 lymphoma cells and BC3H-1 muscle cells--to examine the regulation of beta-adrenergic receptors by receptor antagonists. Rather than an increase ("up-regulation") of receptor number that such antagonists often produce, we found that certain beta-blockers elicit a decrease ("down-regulation") of beta-adrenergic receptors. Alprenolol and propranolol, but not sotalol or ICI 118,551, at concentrations of 10-100 nM down-regulated beta-adrenergic receptors 20-70% following 16-20 hours of treatment of S49 or BC3H-1 cells. Several observations suggest that this phenomenon depends upon beta-receptor interaction, including stereoselectivity [(-)-enantiomers more potent than (+)-enantiomers], blockade of the effect by ICI 118,551, absence of down-regulation of alpha-adrenergic receptors in BC3H-1 cells, and lack of a decrease in beta-adrenergic receptor-independent (forskolin-stimulated) cyclic AMP accumulation in S49 cells. The possibility of retained antagonist interfering with receptor measurement was precluded by the fact that the antagonist-induced decrease in receptor number required several hours incubation and occurred without a prominent change in receptor affinity. The ability of the beta-blockers to elicit down-regulation did not correlate with hydrophobicity of the drugs. Antagonist-induced down regulation of beta-adrenergic receptors did not occur in S49 lymphoma cells that lack the alpha-subunit of Gs, the guanine nucleotide-binding regulatory protein, thus implying a requirement for receptor-alpha s interaction in eliciting beta-receptor down-regulation.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0009-7330
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
279-85
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Certain beta-blockers can decrease beta-adrenergic receptor number: II. Down-regulation of receptor number by alprenolol and propranolol in cultured lymphoma and muscle cells.
pubmed:affiliation
Division of Pharmacology, University of California, San Diego, La Jolla.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.